Radiolysis of quench-cooled pure and barium doped KNO3 in presence of oxides: effect of particle size

Radiation decomposition studies of quenched pure KNO3 and KNO3 doped with Ba2+ ions in the presence of PbO or Al2O3 as a heterophase impurity showed that the yield of nitrite varied with the particle size of the nitrate. The G(NO2-) values were also found to vary with the mol percent of PbO or Al2O3 in the mixture. Higher yields of nitrite were obtained in the presence of PbO, while in mixtures containing Al2O3, the yields of nitrite were lower in comparison with the G-values observed in the absence of oxide. It is suggested that a larger surface area results in an increased energy transfer at the interface between two neighbouring particles. The results are explained also in terms of electron donor-acceptor properties of the added oxides. (author)